Well, I just had a very good experience with Peter McAlister of McAlister Audio.
I purchased a PP150 stereo amp from an AC member and unfortunately a bunch of things went wrong after the purchase.
The first thing to go wrong was having a main tube somehow go bad from the time I picked up the amp to the time I brought it home and fired it up. I think this was just some bad luck and certainly don't blame Peter or the person I bought the amp from. I e-mailed and called Peter up and he helped diagnose what the issue was pretty much immediately. Peter was very good on getting back to me and he even was willing to talk with me late at night when I could be available.
Once I purchased some new tubes, everything was working fine. However, two days later, I stopped getting sound from the left channel. Again after communicating with Peter, it was determined that the amp would have to go back to Canada for repair work. Peter was confident he could diagnose the problem quickly and promised a fast turnaround.
Well the amp arrived Friday afternoon and by Saturday morning he had diagnosed the problem. In addition to fixing the problem (the wiring to the rca jack had become loose), Peter performed some upgrades and fully checked out the amp. He did all of this over the weekend and kept me in the loop via e-mail.
On Monday the amp was packed up and shipped back to me. So my amp wasn't even at Peter's place for a full business day...that's fast and excellent customer service!!

I think the above would be classified as very good service and frankly is something I would expect as a customer (yes, I am pretty demanding customer as many AC vendors already know). However, I wasn't really a customer of Peter's. I bought this amp used and not directly from Peter. He certainly didn't have to treat me this way. It is clear from
my dealings with Peter, that he is a man who not only stands behind his product, but he genuinely wants people who own his products to be happy with them.
While it stunk that I had a few issues right out of the gate, I look forward to finally being able to hear what the PP-150 sounds like.
Thank you Peter for the excellent service and support.

George